
export function sideBarTool (arr) {
    var arr2 = []
    arr.forEach(item => arr2.push(item.substring(0,3)))
    for ( var i = 0 ; i < arr2.length ; i++ ) {
        for( var j = i+1 ; j < arr2.length ; j++ ){
            if (arr2[i] === arr2[j]) {
                arr2.splice(j, 1)
                j -- 
            }
        }
    }
    return [...arr, ...arr2]
}